报告人简介：

Prof. Takashi Hibiki received his BS in 1985 with the highest distinction and Ph. D. in 1990 from Osaka University, Japan.  He is currently a Professor Emeritus of Purdue University in the US.  Prof. Hibiki was an instructor and associate professor at Kyoto University from 1990 to 2006 and a full professor at Purdue University from 2006 to 2018.  Prof. Hibiki is known as an international expert of two-phase flow modeling and developed more than 90 constitutive equations for two-phase flow analysis.  He has authored 253 journal papers and 192 conference papers, and one of his research paper is ranked as No.1 of most cited articles in the International Journal of Multiphase Flow.  Prof. Hibiki was named as Osaka University Global Alumni Fellow in 2015 and American Nuclear Society Fellow in 2011 and received numerous awards internationally.

内容介绍：

In view of the quality assurance of two-phase flow simulations, CSAU (Code Scalability, Applicability, and Uncertainty) methodology and code V & V (Verification and Validation) have been proposed.  The estimation of simulation uncertainty is indispensable in using best-estimate computational codes.  A key of successful two-phase flow simulations is to use the state-of-the-art constitutive equations to close the mathematical system used in two-phase flow analyses.  The advanced constitutive equations should be developed based on ‘‘physics” behind phenomena and should consider scaling parameters which enable their application beyond test conditions used for a code validation.  Two-phase flow simulations in a rod bundle is important in various industrial apparatuses such as heat exchangers and nuclear reactors.  Constitutive equations for two-phase flows in a vertical rod bundles have been advanced in recent five years.  In view of this, this seminar provides a comprehensive review of most advanced constitutive equations for two-phase flow analyses in a vertical rod bundle.  The constitutive equations of two-phase flow parameters reviewed in this seminar are flow regime map, void fraction, void fraction covariance and relative velocity covariance and interfacial area concentration.  In addition, an exact formulation of one-dimensional momentum equation in two-fluid model considering void fraction distribution is discussed.